added new experimental data for 2dof, 4dof and youbot arms. Experiments were conducted under different combinations of X/Y constraints, beta/fext control. For instance for youbot arm (data in tempTest files) there are combinations for xbeta-yfext-zfext control with X constraint. Also added first experiments with posture control for 4dof under X constraint and one of the joints controlled through computed torque like controller.
added some minor comments